Malicious PDF — malware analysis report

Static analysis result for SHA-256 b12af83cc223d318…

MALICIOUS

PDF

68.4 KB Created: 2021-09-24 17:09:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b376de014bf4136d429caf69a813603d SHA-1: a236c9d6226f149f435f11db5be09b9985caca1b SHA-256: b12af83cc223d31853761387014c266067f7ab24daeffa1e4869a1f59764a214
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, with several pointing to compromised WordPress upload directories and other disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm on disposable hosting and compromised CMS sites suggests an attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/xaxerexigamu.pdf In PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/lejujivaxuvaninobun.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/161438c1a65396---26144701572.pdfIn PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/88744463291.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16148011c076d6---2350011832.pdfIn PDF document text
    • http://hainfelderteich.at/zekopepilate.pdfIn PDF document text
    • http://kino-cosmik.ru/sadm_files/gimoxijibowor.pdfIn PDF document text
    • http://studiocommercialedelpiano.it/userfiles/files/74723945227.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/16148625dd5137---vadozazixofuvifupifako.pdfIn PDF document text
    • https://bisleri.genefied.co/ckfinder/userfiles/files/16374092723.pdfIn PDF document text
    • http://roland-toys.eu/userfiles/file/38061799263.pdfIn PDF document text
    • http://budoprojekt.eu/obrazy/file/93161763115.pdfIn PDF document text
    • https://jfava.gemwareserp.com/userfiles/file/73500752939.pdfIn PDF document text
    • http://www.deewanalarab.com/up_imgs/78573030748.pdfIn PDF document text
    • http://veiligheidssloten.nl/ckfinder/userfiles/files/kivipupilovamefalesodizo.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/7660829384.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/84134452333.pdfIn PDF document text
    • http://pinxedien.net/upload/files/nalagasowavadirufetunut.pdfIn PDF document text
    • http://bebaldebaran.eu/userfiles/files/8682146022.pdfIn PDF document text
    • http://langfordfinancialservices.com/userfiles/files/pinawalomopolubizaw.pdfIn PDF document text
    • https://signika.pl/Upload/file/82961622656.pdfIn PDF document text
    • https://full-flavors.com/img/Data/file/kamijavigibika.pdfIn PDF document text
    • http://pazarziraat.com/userfiles/file/70017934153.pdfIn PDF document text
    • http://leicesterbiketec.com/userfiles/file/tawusigejesujudekisazexom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=api+key+for+android+appPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000aef0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEF0 10368 bytes
SHA-256: d7d281534c1571110132cb5b7ae3ce69264d9334f8310a5f020ae6fca2f1a62a
font_01_sfnt_off0000c67a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC67A 15012 bytes
SHA-256: 320cc75ba246a3e79c9badbde1e6395226bc5c9d3fc381cb6e3c9bdbf407b4fa
font_02_sfnt_off0000ebc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1